564 CLASS XVII. 



is found the articulation for the preceding second joint. This second 

 joint has ahnost the form of a triangular prism, is flat below and 

 excised on the outer side, so that the last joint of the finger when 

 at rest lies in it\ Whenever the flexor muscles on the inferior 

 surface of the foot, attached by their tendons to the last joint of 

 the finger, move that joint, the erect claw is drawn forward and 

 downward. When at rest the last joint is supported by two elastic 

 ligaments, which at the back of the hand proceed from the first 

 and second phalanges to the upper margin of the last. 



Only in man and in most of the quadrumanous mammals can 

 the thumb be moved separately and placed at a distance from and 

 opposite to the other fingers; but even in the apes the hand is 

 imperfect, for the thumb is shorter. In some the thumb is even 

 wanting, or there is only a small ossicle on the inside by which it 

 is represented^. 



The hind limbs are connected with the trunk more firmly than 

 the anterior. Here in place of the scapulae are the ossa innominata, 

 which are attached immoveably to the sacrum. The three bones 

 which make up the os innominatum (the ilium, ischium and pubis) 

 are present in the embryo, and also in young animals as distinct 

 bones. The pubic bones are united with each other below; yet in 

 some, as the mole and many bats, they remain separate. In different 

 mammals the ischia also become united with each other and with 

 the pubic bones. In the marsupiate and monotrematous animals 

 a triangular, flat, moveable bone is attached to the anterior margin 

 of the pubic symphysis on each side, and has its point directed 

 forward. In the cetaceous animals traces alone of innominate bones 

 are found, which are remote from the vertebral column, and are 

 connected with the rest of the skeleton by muscles only ; the other 

 bones of the posterior extremities are wanting. 



A deep articular cup at the outside of the innominate bone 

 receives the head of the thigh-bone. This bone in most mammals 



1 Thia excavation is erroneously stated by Cdviek to be on tbe insids of the second 

 joint. Zef. d'Anat. comp. i. pp. 311, 312, and ed. 2, i. p. 434. 



2 Compare on the fingers in mammals Cuvieb Leg. d'Anat. comp. i. 309 — 314, ed. 

 sec. I. 43'2 — 437 ; Meckel Syst. der vergl. Anat. 11. 2, s. 408 — 421; Dumkril Ueher 

 die verschiedencn Formen der dussersten Phalangen bei den Sdugethieren in Reil's 

 Archiv, VII.1807, s. 301 — 316, with figures (translated from the Magas. eiu:ycl., Annee 

 VI. Tome I. No. 3). 



